Alert archive / Maryland / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 109, NWS Philadelphia/Mount Holly

July 18, 2012Caroline County, Queen Anne's County, Talbot County, Maryland; Kent County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 18, 2012, 6:23 PM EDT for Caroline County, Queen Anne's County, Talbot County, Maryland; Kent County, Delaware. It was in force for 37 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 18, 2012, 6:23 PM EDT (22:23 UTC)
Expired: Jul 18, 2012, 7:00 PM EDT
In force: 37 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Kent County, DE, Caroline County, MD, Queen Anne's County, MD, Talbot County, MD

The radar

The Dover AFB radar (KDOX), 34 km from the middle of the area, began a volume at 22:24 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Jul 18, 6:28 PM EDT	TSTM WND DMG	Goldsboro, MD	TREES REPORTED DOWN IN GOLDSBORO.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 18, 12:41 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.4 hours before the alert went out and 63 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 884 J/kg
Mixed-layer CIN: -169 J/kg
Mixed-layer LCL: 1666 m above ground
0-6 km bulk shear: 9 kt
0-1 km storm-relative helicity: 4 m²/s²
0-3 km storm-relative helicity: 10 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

412 
WUUS51 KPHI 182223
SVRPHI
DEC001-MDC011-035-041-182300-
/O.NEW.KPHI.SV.W.0109.120718T2223Z-120718T2300Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
623 PM EDT WED JUL 18 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN KENT COUNTY IN CENTRAL DELAWARE...
  CAROLINE COUNTY IN EASTERN MARYLAND...
  NORTHEASTERN TALBOT COUNTY IN EASTERN MARYLAND...
  EASTERN QUEEN ANNE'S COUNTY IN NORTHEAST MARYLAND...

* UNTIL 700 PM EDT

* AT 617 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM SUDLERSVILLE TO OAKLAND TO MATTHEWS...OR ALONG A LINE
  EXTENDING FROM 22 MILES WEST OF DOVER TO 21 MILES NORTHEAST OF
  EASTON TO EASTON...AND MOVING EAST AT 20 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  SUDLERSVILLE...MATTHEWS AND RIDGELY AROUND 630 PM EDT...
  GRIFFIN AND GOLDSBORO AROUND 635 PM EDT...
  GREENSBORO AROUND 640 PM EDT...
  SANDTOWN AROUND 645 PM EDT...
  DENTON AROUND 650 PM EDT...
  HARTLY AROUND 655 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...LARGE HAIL...AND DEADLY CLOUD TO
GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...FREQUENT CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE
ENOUGH TO BE STRUCK BY LIGHTNING.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
WEDNESDAY EVENING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND
NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 3883 7610 3904 7592 3921 7598 3924 7556
      3904 7548 3883 7563 3883 7572 3875 7572
TIME...MOT...LOC 2222Z 270DEG 16KT 3916 7591 3904 7586
          3882 7601

$$
DRAG

1 follow-up statement

325 
WWUS51 KPHI 182236
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
636 PM EDT WED JUL 18 2012

DEC001-MDC011-035-041-182300-
/O.CON.KPHI.SV.W.0109.000000T0000Z-120718T2300Z/
KENT DE-TALBOT MD-CAROLINE MD-QUEEN ANNE'S MD-
636 PM EDT WED JUL 18 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM EDT
FOR EASTERN QUEEN ANNE'S...CAROLINE...NORTHEASTERN TALBOT AND WESTERN
KENT COUNTIES...

AT 634 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM BARCLAY TO GOLDSBORO TO MATTHEWS...OR ALONG A LINE
EXTENDING FROM 19 MILES WEST OF DOVER TO 17 MILES SOUTHWEST OF DOVER
TO EASTON...MOVING EAST AT 20 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  MATTHEWS...GRIFFIN AND HENDERSON BY 645 PM EDT...
  SANDTOWN...TEMPLEVILLE AND MARYDEL BY 650 PM EDT...
  DENTON BY 655 PM EDT...
  HARTLY AND HAZLETTVILLE BY 700 PM EDT...

THE OUTFLOW WESTERLY WIND GUSTS AHEAD OF THE PRIMARY LINE OF THE 
THUNDERSTORMS MAY ARRIVE A BIT SOONER THAN INDICATED. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE
ENOUGH TO BE STRUCK BY LIGHTNING.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
WEDNESDAY EVENING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND
NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 3883 7610 3904 7592 3920 7594 3924 7556
      3904 7548 3883 7563 3883 7572 3875 7572
TIME...MOT...LOC 2236Z 270DEG 16KT 3915 7586 3904 7578
          3883 7599

$$

DRAG

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 18, 4:37 PM EDT	Special Weather Statement	PHI	Kent	23 min
Jul 18, 4:47 PM EDT	Special Weather Statement	PHI	Cecil	28 min
Jul 18, 5:20 PM EDT	Special Weather Statement	PHI	Queen Anne's	40 min
Jul 18, 5:35 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Queen Anne's	25 min
Jul 18, 6:06 PM EDT	Severe Thunderstorm Warning	PHI	Caroline, Kent, Queen Anne's, Talbot	39 min
Jul 18, 6:26 PM EDT	Areal Flood Advisory	PHI	Caroline, Kent, Queen Anne's, Talbot	68 min
Jul 18, 5:47 PM EDT	Special Weather Statement	PHI	Kent, New Castle	58 min
Jul 18, 6:01 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	17 min
Jul 18, 6:48 PM EDT	Special Weather Statement	PHI	Kent	12 min
Jul 18, 6:57 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	82 min
Jul 18, 6:57 PM EDT	Severe Thunderstorm Warning	PHI	Kent	17 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2012 Severe Thunderstorm Warnings in Delaware, 2012 Every severe thunderstorm warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.